Matthew’s all about cost-effective erosion control

Gully erosion is an environmental challenge widespread across Queensland landscapes.

Gully formation is closely linked to soil types and situations where the topsoil is denuded and erosion-prone subsoils are exposed to direct contact with rain drop splash and water flows. 

Erosion-prone soils have a tendency to “dissolve” or disperse and slump very quickly when in contact with water.

They’re a significant contributor of sediment in waterways and to the Great Barrier Reef lagoon. That’s why many of our projects address gully erosion.

It’s a priority for Matthew Crowley, who has a property west of Charters Towers. He’s keen to find cost-effective ways to control erosion he can install and maintain with his own machinery.

Matthew has carried out a number of projects to address erosion spots. 

These photos tell a story about a day he and NQ Dry Tropics Soil Conservation Officer Bernie Claussen spent addressing gully erosion, a gully with two actively-eroding heads impacting an access road. The catchment area was about one hectare.

Matthew was keen to use materials he already had on his property — wire mesh, hay made with speargrass, and a small amount of ironstone gravel. 

The cost-effective solution involved building whoa boys on the road to reduce and divert the flow of water away from the gully heads and into stable drainage lines, and to stabilise the gully with a series of leaky weirs. 

Installing chutes and drop structures weren’t considered because of the associated costs. There was no available rock, and gravel was limited, and because it was fine in structure, Bernie and Matthew were concerned it could run downhill fairly quickly after first rain. 

Many years ago, tyres had been tried to slow the flow of water; and although they worked to some degree, water was directed around the objects, removing more soil. 

The leaky weirs were made with two lengths of wire mesh, 100ml by 60ml, which were staggered to make the aperture smaller. Hay was then rolled out, and a couple of loads of gravel placed on top. 

The aim is for the hay to hold the gravel until vegetation starts to grow. This will make a bit of a check for the sediment that comes down off the ridge during rain events.

It’s now a waiting game. Although quietly confident, Bernie and Matthew said they were uncertain about the success of their efforts and were eager to see the results following a significant rain event.

This work was completed through the NQ Dry Tropics Healing Country 2.0 project, funded through the Queensland Government’s $33.5 million Reef Assist program under the Queensland Reef Water Quality Program.

It aims to achieve a range of environmental outcomes to improve water, soil health, condition of native ecosystems and contribute to the productivity of grazing enterprises.

Matthew constructed whoa boys on the road to reduce and divert the flow of water away from the gully heads and into stable drainage lines.

This work was funded by The Herding Change Through Grassroots Recovery project, funded through the partnership between the Australian Government’s Reef Trust and the Great Barrier Reef Foundation, and through the Queensland Government’s $33.5 million Reef Assist program under the Queensland Reef Water Quality Program.